1. Field of the Invention
The present invention relates to light emitting diode drivers, and more particularly, to a light emitting diode driver having a protection function that activates hiccup mode for a predetermined period of time when a light emitting diode performs an abnormal operation to thereby protect the light emitting diode.
2. Description of the Related Art
In general, liquid crystal displays (LCDs) include backlight units that employ cold cathode fluorescent lamps (CCFLs) as light sources. However, CCFLs may cause environmental pollution since they use mercury gas, have low response speeds, and low color reproducibility. Besides, CCFLs make it difficult to reduce the weight, thickness, and size of LCD panels.
Therefore, light emitting diodes (LEDs) have currently been positively used in display devices. When compared to CCFLs, LEDs are environment friendly, have a high response speed of several nano seconds, are effective for video signal streams, can be impulsively driven and have a color reproducibility of 100% or more. Furthermore, the brightness and color temperature of LEDs can be varied by controlling the amount of light emitted from red, green, and blue LEDs, and LEDs make it possible to reduce the weight, thickness, and size of LCD panels.
It is necessary for backlight units having these LEDs to use LED drivers that supply electrical currents to the LEDs to drive them.
LED drivers initiate latch mode when abnormal voltage or an abnormal current is applied to the LEDs, so that the LED drivers maintain latch-off mode when power is not physically reset without any time to return to a normal state.